Spark plug



Patented `luly 3," 1923A.

A ,UNITEDSTATE-S,

Y SPARK ZPLUG,

rppiication ined April e, '1922. seriall 55o,of5if yTo all whom #may con-cem.'

' Be it known that we, JAMES L. BRocKNEY and` CHARLES E. GEORGE, both citizens'of the' United States, residing lat Detroit, in

the county of Wayne'and State of Michigan, "have l`invented certain new and useful Iniprovements Vin Spark iPlugs, of which A'the following is a specification. j j

This invention relates to spark plugs and has special reference to a spark plug with a '.movable electrod'e terminal.

In the construction of spark plugs it is wherein is littedr'a porcelain insulatorV 11.A held 'securely in place by means of al nut 12. This insulator terminates well above` well recognized' lthat'fstationary electrode terminals soon have the sparking points coated with vcarbon l deposits or 'otherwise deterioratedso'that .they no longer are effective for ignition purposes. It has been sought to overcome the objections to this type of spark plug by proving a movably supported electrode terminal such as a pendulum, loose ball or the like but these have not been ,found entirely satisfactory. It has also been sought to-overcome the inherent deciencies of spark plugs by the provision of an electrode terminal in the form of a small propeller ywhich is caused to rotate by the gases iowing vpast it. This form has been found fairly good when'new but is open to the very serious objection oi" having a. tendency to sticker freeze and thus become, in effect, a stationary electrode.

The principal and most important object of the present invention is to provide animproved form of spark plug embody-v ing the best feature of the propeller provided plugs but having in addition certain novel arrangements wherebyrthe defects due to sticking and the like are overcome.

With the above and other objects in view, the invention consists in general of certain novel details of construction and combinations of parts hereinafter fully described, illustrated in the accompanying drawings, and specifically ',claimed. Y

In the accompanying drawings, like characters of reference indicate like parts in' the several views, and

Figure 1 is a longitudinal medium section through a spark plug constructed in accordance with this invention, the view being on a scale giving the plug device the length and breath of the standard size commonly used in gasoline and other vlike engines.

Figure 2 isv an end view showing the sparking terminals.

vFigure 3.

Figure 3 isa longitudinalsection 'i part 'Hoff Y the 'f central electrode the lower sleeve.y y Y y Y Figure 4L is asection on the lined-1rof Figure 3,.V u Y 'Figure 'isa In the enibodiinentof vthe inventionhere.- in disclosedI the "improvenientsv have been shown in connection'with a plug ofwell'known:make, y t

This spark plug 'hasthe usual shell 10 Y i y 1 ,4 ,745..v

section on the" line 5-7-5" of i I ystandard spark the lower or spark gapenddof theshell whichy is` provided at lthisv endwith -anren larged ychamber 14. The insulator is provided with the usual lcentral opening 15 which terminates below in an enlarged portion 16 and through this opening 15 eX-X.

tends the central electrode whichjconsists f of a rodv17 provided, at the lower part Y just below the4 openingvl, with a collar 18 which bears against a suitable packing- 19.

Tlie upper end of the electrode is threaded Y and projects above the insulator. On this'.

threaded end is providedthe washer'20 and nut 21, for holding the electrode rigidly in position, andthe binding nut 22 for the wiring terminal.

construction throughout.

It is to be noted that the rod 17 is continucdbelow the collar 18 and on this lower end is mounted a long sleeve 23 which eX- tends up into the opening 16 and is so proportioned with respect to the rod that it can revolve freely thereon without possibility of l.

sticking, this arrangement beingindica-ted in an exaggerated manner in the drawings The parts just described are practically of ordinary and well known by showing considerable clearance between Y these parts although, in actual construction,- the necessary clearance is obtained by mak ing the bore of the sleeve a few thousandths of an inch greater than'the diameter of the tact with flame or explosion, and is thus f kept from heating toogreatly. Also the rod 17 is protected so tha-tit is kept relatively cool, Due to these features freezing of the vsleeveonr'the rod is practically impossible.

Atfthe lower end' of the sleeve isa periplieral groove 25 whereinv is itted the hubk of a propeller 26,this hub also having properV clearance to permit free revolution on the sleeve. These parts are assembled by forming the sleeve with areduced end, slipping the propeller in place and beading over the end ofthe vsleeve to form the groove. `Bue to this construction,'ithe sleeve beingkept relatively cool7 thereis ractically no tendeney of the propeller to reeze? on the sleeve. Thus, owing to the double precaution taken, it is found in practice that the propeller never refuses to vfunction by revolving in the end of the shell at each explosion.

Itis obvious that the ends of the Vpropeller blades` arefso Vspacedfrorn the'shell that the proper spark gap is obtained. y A

There has thus been provided a sirnple and eloient device of the kind described and for .the purposes speciied. Having thus described the invention, what is claimed as new, is

.l'.-In aspark plugla shellV forming the outer electrodeya central electrode Vwithin the shell and insulated therefronnalsleeve revolubly'mounted onth'e lower end *of the" central electrode, and apropeller mounted v outer electrode an insulator vwithin said'sliell v ends spaced vfrom thershell to and having Van Vopening therethrough-ter!" -minatingv in an enlarged portion at its lower end, a rod passing through said openingand 'forming' afcentral electrode, a sleeve revoluble on said rod and having its major po'rtion located in the enlarged portion of the ly cool, .and a propeller at the lowerend of the sleeve within said shell and having blade e ends spa-eed from the wallpof the shell to form spark gapsysaid propeller being 'freely revoluble on thel sleeve.

In testimony whereof'we aHiX our signatures. -v Y;

Y CHARLES E.' GEORGE opening whereby to Ykeep'the sleeve relative- ;y JAMEs LjBRo'oKNEY f 

